Rigorous correlation for CO2 mass transfer flux in reactive absorption processes

Mass transfer flux of CO2 in reactive absorption processes depends on mass transfer variables of both liquid and gas phases. In this work, a new rigorous correlation for calculation of CO2 mass transfer flux in reactive absorption processes was developed based on the variables. The correlation parameters including film parameter, CO2 loading, concentration ratio, pressure ratio, film thickness ratio and diffusion coefficient ratio were determined using Buckingham Pi-theorem. Experimental data of CO2 reactive absorption in piperazine solution were used to evaluate the correlation. The data used in calculating the correlation constants are temperature in range of 40-100 °C, partial pressure of CO2 in range of 18-66,330 Pa, CO2 loading in range of 0.226-0.412 mole of CO2 per mole of amine and amine concentration of 2-8 molal (Dugass, 2009). The average absolute relative error for the presented correlation is 5.8% which infers high accuracy of this correlation compared to the previous correlations reported based on enhancement factors. The results showed that increasing the temperature and CO2 loading has negative effect on CO2 mass transfer flux. Also the results indicated that on increasing partial pressure of CO2 and piperazine concentration, the rate of mass transfer was increased.